The Tintin books have a running gag in which Captain Haddock picks up a glass of the local firewater, overconfidently chugs it and then almost chokes to death from the strength of the hooch. He does it with aguardiente, with spadj (a Balkan loony juice, which, I think, Hergé made up) and with the national drink of Peru, pisco. That happens in Prisoners Of The Sun, and as a result I've been mildly curious about pisco since before I was old enough to drink. I stress "mildly" – after all, the stuff does make Haddock gag.

It eventually came time to scratch that particular itch. My opportunity came at Ceviche in Soho. Pisco is a specialty of the place, which is somewhere you can go for a drink and a bite to eat as much as it is a restaurant – a fact that contributes to the nicely casual, relaxed atmosphere. There's a large list of macerados, or pisco infusions, as well as a list of pisco cocktails. I tried a chilli macerado; my friend had one infused with sour cherry; they were delicious and tasted of chilli and sour cherry, respectively. So it turns out Captain Haddock was a wimp.

Peruvians claim the dish ceviche as their own. I subscribe to the rival theory that it comes from Polynesia, but I can see why Peruvians would want it, since it's such an interesting thing to eat: fish "cooked" with citrus, which makes the proteins coagulate in the same way that heat does. (The Polynesians, who travelled huge distances by canoe, would have had strong reasons for inventing a dish that allowed them to cook fish without using firewood. I'll shut up about this now.) Ceviche is simple in conception, has great possibilities for subtlety and complexity in execution, gives a strong kick of flavour, and depends on fresh ingredients – so it's very modern. I can see why you'd name a restaurant after it, rather than the other great Peruvian specialty, cuy. That's guinea pig to you. Peruvians get through 65 million of them a year. It's perfectly legal to cook them in the UK, but I've never heard of anybody doing it.

I really like ceviche, and I really liked Ceviche. They have a ceviche bar at the restaurant, and do a good job of stressing the variety of which the dish is capable. All feature tiger's milk (leche de tigre), the marinading emulsion of lime, chilli and salt that is the star ingredient in the Peruvian way of ceviche (it's sometimes served in a shot glass on the side, too, I'm told). Some tiger's milks are sharper and more acidic, some hotter and some milder; the balance of fish and tiger's milk is part of the drama and interest of the dish. I particularly liked the Don Ceviche, small chunks of sea bass with ají amarillo chilli in the milk and ají limo chilli on the fish, and it was interestingly different from another sea bass dish, "Barranco I Love You". That's a silly name but it was a serious starter in which the bass was sliced thin and served with an ají amarillo tiger's milk and pieces of intriguingly tasty giant Peruvian corn.

There's lots to be interested in after the ceviche. Grills are big in Peru, as elsewhere in Latin America; here, they feature in proteiny skewers of meat. I've only eaten beef heart in slow-cooked versions, but at Ceviche it comes in a thin slice on a skewer, and very good it is, too, roughly like calf's liver in flavour, but with a chewier, denser texture. Other dishes included a duck confit with lots of coriander and rice cooked in beer with more of that super-authentic corn. Wok-cooked strips of beef came with a soy-oriented "saltado" sauce – the dish showed the Chinese influence that is one of the things that makes Peruvian cooking so interesting. It was also the dish we liked best. The only odd or bland note was a side of beetroot purée with a coriander-oriented cake of mashed potato; this was the only spud in the meal, which is odd given that they come from Peru.

Pisco returned as a theme at pudding, in a spirit-soaked cinnamon sponge, served with a lovely dulce de leche ice-cream – the sort of dessert that vanishes as soon as it hits the table. I left Ceviche happy, and wanting either to go back or to visit Peru. I know which is likelier.